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Sample A-31-89
NavDat sample number 48648 · SYENITE
Sample
| Sample ID | A-31-89 |
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| Rock name | SYENITE |
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| Rock type | PLUTONIC |
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| Composition | INTERMEDIATE |
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| Material | IGNEOUS |
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| Comment | dike contains large, flow-aligned, altered sanidine phenocrysts in a groundmass of hb, augite, feldspar, and ox |
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Location
| Latitude | 47.1889 |
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| Longitude | -111.796 |
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| Location | exposed along Chestnut Valley road, 1 km NE of Halfbreed Rapids |
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| State / province | Montana |
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| Volcanic field | Adel Mountain Volcanics dike |
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Age
| Age (Ma) | Error | Min | Max | Geologic age | Dated by |
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| 73.17 |
|
72.75 |
73.59 |
|
|
Analyses
No chemical analyses are stored for this sample.
References
- Harlan, Stephen S; Snee, Lawrence W; Reynolds, Mitchell W; Mehnert,Harald H; Schmidt, R G; Sheriff, Steve D; Irving, Anthony J (2005) U. S. Geological Survey Professional Paper, Report: P 1696, 29 pp.,2005
